Box construction



July 10, 1934. J. R. WATKINS 1,965,871

BOX CONSTRUCTION Filed March 25, 1931 Patented July 10, 1934 PATENT OFFICE BOX CONSTRUCTION James R. Watkins, Chicago, Ill., assignor, by mesne assignments, to Chicago Mill and Lumber Company, Chicago, 11]., a corporation of Delaware Application March 25, 1931, Serial No. 525,065

3 Claims.

This invention relates to shipping boxes and similar constructions and more particularly to a box of the so-called wirebound type, comprising a plurality of panels made up in blank form and capable of being readily set up by securing together the free ends of wire or other binding means used for reinforcing the box.

One object of the invention is to provide a box of the class described having a substantial portion of the interior thereof free from frame members or cleats and in which certain of the frame members or cleats are arranged on the exterior of the box.

Another object .of the invention is to provide a 5 novel cleat construction in association with the exterior of the box permitting the manufacture of the box with one or more continuous lines of cleats on the exterior, without distorting the side walls, the cleats being reinforced with wire or similar binding means, secured thereon in a well known manner.

A further object of the invention is to provide a box construction well suited to manufacturing operations in that it requires no extensive modification of existing equipment for making boxes of this type.

A still further object of the invention is to provide an improved method for making the blank of a box having the above mentioned characteristics.

To these and other ends the invention resides in certain improvements and combinations of parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawing:

Fig. 1 is a schematic view illustrating the relationship between the blank and the conveyor after completion of the stapling operation;

Fig. 2 is a perspective view of the box, set up;

and

Fig. 3 is a fragmentary sectional view of an upper corner of the box taken along the line of the slots formed in the top cleats.

Similar lreference numerals throughout the several views indicate the same parts.

The present invention, as disclosed, comprises essentially a wirebound box, having side walls and outside cleats adjacent its upper edges, said cleats having cut-away portions or slots therein adapted to receive the wire when the box has been setup.

Referring more particularly to the drawing, there is shown at 10 in Fig. 1 the blank from which the box is formed. This blank comprises fourpanels 11, 11 and 12, 12. The panels may be formed from any suitable material compatible with the article to be packed, but in the present instance it is preferred to use relatively thin wood or multi-ply wood veneer, either in strips or in pieces of the size required for an entire panel.

Wood cleats 13 of substantial strength and stiffness are disposed on the panels 11, 11 and 12, 12 adjacent their upper edges. These cleats are preferably secured to their respective panels as by means of nails or stitches, not shown, driven through the panels into the cleats.

For the purpose of providing a corner construction which will not slip when the box is set up, it is preferred to so shape the panels and cleats that one panel will abut the edge of its adjacent panel and-the cleat on the latter panel will abut the edge of the first mentioned panel. To this end, panels 11, 11 are preferably made of a width equal to the length of the respective cleats 13 to be secured thereto and the panels 12, 12 are somewhat less in width than their attached cleats. The difference in dimension between the panels 12, 12 and their cleats 13, 13 is preferably equal to the thickness of the material from which the panels are made, so that when the box has been set up the panels and cleats will interfit as indicated clearly in Fig. 2.

For the purpose of joining the side walls into one unitary blank, capable of being set up in box formation, there is secured a plurality of wires, 14, 15, 16, 1'7, by means of staples or the like, 18. The operation of applying the binding wire to the box may be carried out by hand but is preferably done on a conventional wirebound machine, where the operation is more or less continuous. It will be understood that the wires between complete box blanks are severed so as to provide a suflicient amount of wire that the ends can be twisted together in the setting up operation.

From the description this far, it is apparent that there is provided a box construction having a substantial part of its inner surface free from cleats or other obstructions, so that spacing between the various panels substantially conforms with the outside dimensions of the article to be contained therein. This is accomplished because of the fact that the reinforcing cleats 13 are on the outside instead of the inside.

By reference to Fig. 1 it is noted that the cleats 13 are snugly abutted during the blank forming process. This is necessary in order to obtain the advantageous corner construction illustrated in Fig. 2. As the abutted cleats, during the operation of setting up the box swing relative to each other, substantially about their inner corners, it is clear that means must be provided to compensate for the increase of the distance between the adjacent outer corners of the cleats so that Q the wire 14 will not be unduly stretched or broken in setting up the box. To accomplish this I preferably provide each cleat with a cut-away portion or slot 19, extending from substantially the inner comer of the cleat and terminating at the outer surface of the cleat some distance from its end. Upon setting up the box by swinging the side walls toward each other, with the cleats on the outside of the box, it is apparent that the wire will contact the surface 20 of the cut-away portion or slot and thus permit the wire to approach the outer corner formed by the meeting edges of adjacent panels 11 and 12. Thus, instead of the wire having to pass around the outer comers of the cleats, which would entail extreme stretching and breaking of the wire, it will merely contact the surfaces 20, 20 and considerably reduce the stretching tendency thereof.

The surface 20 of the cut-away portion or slot may either by formed as a straight line surface or somewhat curved. For the sake of simplicity of manufacture, the straight line surface is considered preferable.

In the practical application of my invention, I have found that it is necessary to keep the slope of the cut-away portion or slot within certain limits in order to insure an efficient and workable construction being provided. In making tests, I have utilized annealed iron wire of substantially 14 gauge, of a breaking strength of approximately 264 to 280 lbs. Cleats and panels were made from clear red gum lumber or other varieties of wood having substantially the equivalent strength and stiffness.

The cleats employed had a. thickness of and a width of 1 The panels employed were either three ply veneer or strips of thin lumber of a thickness of approximately The binding wire was secured to the cleats by means of 18 gauge staple wire, the grip of the staple being such as to substantially prevent slippage of the binding wire on the cleats. When using materials as just described I preferably construct the cut-away portion so that its length is approximately 10% greater than the distance between the outer corners of the cleat and the juncture of the surface 20 with the outer face of the cleats, this being the distance indicated by letters A, B in Fig. 3.

When the surface 20 is made as a straight bevel, it is preferable to give it an angularity of from 20 to 30 with the inner surface of the cleat. It has been found by test that this angle may be increased up to about 35 or 36 which causes a stretch of the wire at the corners of the cleats of approximately 18% to 20%. When the angle of the surface 20 is increased to around 40 or 45, the force which must be exerted to bring the cleats to right angle relationship is so great as to exceed the elastic limit of the wire and cause it to break or become so weakened as to readily break upon receiving a relatively slight blow.

In order to determine the permissive limits in another manner it may be stated that the combined length of the bearing surfaces of the cutaway portions (that is, the combined lengths of the bottoms of the slots) should be preferably not more than about 120% of the distance between the points of juncture of the plane surfaces of the cleats with the outer terminals of the bottoms of the slots. In other words, safe limits are maintained by so forming the grooves that the distance between their outer terminals multiplied by 1.20 approximately represents the maximum combined lengths of the bottoms of the grooves. From still another viewpoint, the permissive limits may be determined by keeping the angle between the bottoms of the pairs of slots greater than approximately 110 when the cleats are in end-to-end abutting relation and lying in the same plane. In other words, the sum of the angles of the slots relative to the panels should be less than 70, the individual angles of the slots on each cleat being preferably less than 45.

In a wire capable of stretching without breaking, it has been found that there is not sumcient resistance to properly hold the corners of the crate together against the weight of the contents. A certain amount of the difference between the surface 20 and the points A, B, is compensated for by the fact that the wire is somewhat embedded in the surface of the wood at the juncture of the surface 20 and the outer face of the cleat and also at the meeting ends of the cleats and the panels.

With the blank in set up condition, to form a completed box, the free ends of the wires 14, 15, 16, 17 are twisted together, substantially as indicated in Fig. 2. The ends of the wire 14 are preferably so arranged as to permit them to be twisted together at a point somewhat removed from the end of the slot 19 on the outer face of a cleat 13.

If desired, one or more sets of reinforcing cleats, as indicated at 21, 21, see Fig. 2, may be se- 'cured on the inside walls of the box. The cleats 21, as shown, serve the purpose of a nailing base for the bottom 22 of the box and other sets of cleats, not shown, will be employed merely for the purpose of strengthening the box and will be 1 used where the character of the article to be packed permits such cleats to be secured on the interior of the walls between their upper and lower ends.

A top closure, not shown, similar to the bottom closure 22, is provided, which is adapted to be nailed to the edges of the cleats 13.

A preferred method of assembling the blank will now be described. The panels, either in the form of complete single pieces or a plurality of strips, are selected and to these panels are secured, as by means of nailing or stitching, the cleats 13 in the relationship indicated in Figs. 1 and 2, so that the alternate panels 12, 12 will terminate short of the ends of their cleats and the remaining alternate panels 11, 11 will have their edges flush with the cleats secured thereon.

After the cleats are nailed in place, the panels are then ready to be handled by the machine for applying the binding wire. This machine may be, in all substantial respects, a conventional wirebound machine, with the exception that one of the stapling heads is raised to operate at a higher elevation than the remaining stapler heads so as to properly attach the wire 14 to the cleats 13.

A wirebound machine similar to the machine disclosed in patent to Babcock, No. 1,371,595, may be employed for the purpose of assembling the panels with the attached cleats. In order to. insure proper spacing of the panels, a plurality of spaced lugs 23, 23 are provided adjacent both sides of the conveyor chain 24, 24.

From the foregoing it is apparent that the present invention provides a box having all the advantages of the ordinary wirebound box, as to rigidity and compactness in shipment and, as well, provides the additional advantage of saving a substantial percentage of the material of the box due to the fact that the panels need only be as large as the largest dimension of the article to be packed, whereas if the frame members are on the inside of the panels, the panels must be as wide as the widest dimension of the article plus the thickness of the inside cleats. The provision of the cut-away portions in the corner of the cleats readily permits the use of the outside cleats without any inward displacement of the side walls and, at the same time, due to the advantageous interlocking corner construction and the fact that the wire at each corner will be somewhat stretched in the setting up operation, a very rigid and sturdy construction will be provided.

Another feature of the construction herein provided is that the cleats form an overhanging portion which can be readily grasped by the fingers in handling the box, either in lifting it or in getting it upon a hand truck so that the handling and shipping of articles in a box of the present invention is greatly facilitated.

One of the most important uses of the box of the present invention is in the shipping of heavy objects of a delicate nature, such as cooling units for mechanical refrigerators, the present box being particularly adaptable because of its light weight, yet extremely strong construction, for such articles.

While the present description sets forth a preferred embodiment of the invention, numerous changes may be made in the construction without departing from the spirit of the invention, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

I claim:

1. A box blank having a plurality of panels of sheet material constituting side walls, a cleat secured to each panel, said cleats being abutted end to end lengthwise of the blank and having inclined slots in adjacent ends thereof the bottoms of which converge in the direction of the panels and meet at substantially the inner line of juncture of the panels and cleats, the bottoms of the slots being inclined at an angle of 35 or less relative to the plane of the panels, a wire disposed on the outer surfaces of the cleats, said wire extending straight along the cleats as well as over the ends thereof, and secured thereto in alignment with the slots while the cleats are in end to end abutting relation, whereby, when the blank is set up to form the side walls of a box, with the cleats on the outside, the wire will be received in said slots, the portions of the wire adjacent the corners of the box being thereby tensioned but without subjecting the wire to such a stress as to cause it to break.

2. A box blank having a plurality of panels of sheet material constituting side walls, a cleat secured to each panel, said cleats being abutted end to end lengthwise of the blank and having inclined slots in adjacent ends thereof the bottoms of which converge in the direction of the panels and meet at substantially the inner line of juncture of the panels and cleats, the bottom of a slot in one of each pair of abutting ends of said cleats being inclined at an angle of less than 35 relative to the plane of said panel, a wire disposed on the outer surfaces of the cleats, said wire extending straight along the cleats as well as over the ends thereof, and secured thereto in alignment with the slots while the cleats are in end to end abutting relation, whereby, when the blank is set up to form the side walls of a box, with the cleats on the outside, the wire will be received in said slots, the portions of the wire adjacent the corners of the box being thereby tensioned but without subjecting the wire to such a stress as to cause it to break.

3. A boxblank having a plurality of panels of sheet material constituting side walls, a cleat secured to'each panel, said cleats being abutted end to end lengthwise of the blank and having inclined slots in adjacent ends thereof the bottoms of which converge in the direction of the panels and meet at substantially the inner line of juncture of the panels and cleats, the angle between the bottoms of adjacent slots being greater than 110 whereby the sum of the angles of the bottoms of the. slots relative to the plane of the panels will be less than 70, a wire disposed on the outer surfaces of the cleats, said wire extending straight along the cleats as well as over the ends thereof, and secured thereto in alignment with the slots while the cleats are in end to end abutting relation, whereby, when the blank is set up to form the side walls of a box, with the cleats on the outside, the wire will be received in said slots, the portions of the wire adjacent the corners of the box being thereby tensioned but without subjecting the wire to such a stress as to cause it to break.

JAMES R. WATKINS. 

